Human Biology

Human Biology Definition

Human biology is the branch of biology that focuses on human beings and human populations; it encompasses all aspects of the human organism including genetics, ecology, anatomy and physiology, anthropology, and nutrition, among others. Human biology is related to other fields of biology such as medicine, primate biology, and biological anthropology.

History of Human Biology

Humans have been focused on understanding themselves ever since gaining higher-order thought processes. One could say that the study of human biology began with the evolution of humans. However, the term “human biology” was not used to describe a separate subfield of biology until the 20th Century. Raymond Pearl, a professor of biometry and vital statistics at Johns Hopkins University, was the first modern biologist to use the term “human biology”. In 1929 he founded the peer-reviewed scientific journal Human Biology, which still exists today.

Much of human biology in the past was concerned with the issue of race. Beginning in the Age of Exploration, different ethnic groups came into contact with each other more and more frequently, and it was during this time that the notion of race began to be developed. During the 19th and early 20th centuries, biologists used the typographical model of race. This concept grouped the world’s human populations into distinct categories based on geographic location and a small number of physical traits. It was based on the work of past biologists. For example, in the 18th Century, father of taxonomy Carolus Linnaeus grouped the world’s people into four categories, going as far as to state that the different racial categories were different subspecies of the human species. The typographical model made broad, inaccurate generalizations about people of different ethnicities, but it was used for around 100 years, until as late as the 1940s. Closely related to the typographical model was the eugenics movement, which aimed to “improve” the genetic makeup of the human race through selective breeding and banning certain groups of people from reproducing. Sterilization programs were carried out in the United States in the early 20th Century. At first these programs were targeted toward the mentally ill, but they expanded to target alcoholics, prostitutes, and even people who were considered promiscuous, feeble-minded, or in chronic poverty. Around 65,000 Americans, the majority of which were minorities, were sterilized against their will. Eugenics lost favor by World War II, especially after the horrors of Nazi Germany and Hitler’s use of eugenics principles became apparent.

In the 1940s, the population model replaced the typographical model. This model was based on the idea that groups of people who have similar traits come from ancestors that mated with each other in distinct breeding populations for thousands of years. However, throughout human history, populations have often migrated and intermarried, so the population model is not wholly accurate. It can really only be used to study the very few isolated groups that exist today. In the 1960s, the clinal model was developed, which states that traits change gradually from one geographic location to the next. For example, the frequency of the B allele in blood types gradually increases as one travels from Europe to Asia. The clinal model can describe many (but not all) human traits. Today’s view, aided by modern genetics research, is that since all humans are at least 99.9% similar to each other, distinct races of people do not truly exist; while there are different ethnicities, race is a social construct.

Currently, the field of human biology is very diverse, but much of the focus of studying humans is now from a genetics standpoint and continues on the path of the many scientific advancements of the 20th Century, such as the discovery of the genetic material DNA and its structure. Some examples of research topics are mitochondrial DNA, which is solely passed down through the maternal line, health disparities between different populations (which may be caused by a variety of genetic and environmental influences), and the evolution and migration of ancient humans.

Human Biology Major

Some universities have bachelor’s degree programs in Human Biology, or Biology with a focus on human biology. Human biology programs leading to a bachelor of arts (BA) degree are designed for students with a specific interest in human biology who want to go on to careers in healthcare-related fields or public policy. However, those who are interested in going to medical, dental, or veterinary school generally should pursue a bachelor of science (BS) degree, which may have more intensive lab-based courses or require more technical courses such as computer programming or mathematics. Some schools offer the choice of either the BA or the BS degree, while at others the human biology program leads solely to a BA or a BS, so it is very important to check with the specific school and program requirements when considering whether to major in human biology.

Careers in human biology include scientific research or being a doctor, dentist, or veterinarian (which the BS degree is generally more suited for), healthcare positions such as being a genetic counselor, occupational therapist, or physician assistant, positions in law and public health. While human biology programs generally focus more specifically on the biology of humans as opposed to other living organisms, there are a wide variety of courses available to take because the field of human biology is interdisciplinary and closely linked to the social sciences. Generally, people who are highly interested in conducting research will often pursue a general biology major, but the human biology major may be helpful in research if one wishes to go on to do biomedical research or become a physician-scientist. Most careers in human biology require further schooling such as a master’s degree, doctorate, or medical degree; the human biology bachelor’s degree is often just the first step to a career in this field.